CHILSEO

In 1618, on the eve of his arrest on charges of treason, writer Gyun Heo foresees his impending fate. He entrusts a copy of The Tale of Hong Gildong to Dol-han, his illegitimate son, and urges Chi-ui Park, who is hiding on Mount Jeombongsan, to remain in seclusion. As Gyun Heo recites the novel's final passage, seven men appear in his vision—the men who will later be executed following the Seven Illegitimate Sons' Rebellion. The story then travels back to 1608. Seven illegitimate sons, despite having passed the civil service examinations and secured government positions, are stripped of their posts because of their social status. They establish a communal residence along the Namhan River in Yeoju, where they live together. Recognizing their abilities and sympathizing with their unjust circumstances, Gyun Heo approaches Yang-gap Seo and the others with a secret proposal to reform Joseon society. Although they share a vision of change, Yang-gap Seo and Gyun Heo soon clash over how to achieve it. Suspicion also grows among the seven men as conflicting interests and hidden political agendas emerge. As their revolutionary plans begin to unravel, questions arise over who manipulated the seven men and whether Gyun Heo himself was merely another player in a larger political scheme. Their story becomes a tragic reflection on ambition, betrayal, and the price of challenging an unjust social order.